* [PATCH v5 0/2] firmware_loader: fix uaf in firmware_fallback_sysfs
@ 2021-07-21 19:00 ` Anirudh Rayabharam
0 siblings, 0 replies; 9+ messages in thread
From: Anirudh Rayabharam @ 2021-07-21 19:00 UTC (permalink / raw)
To: mcgrof, gregkh, rafael, skhan
Cc: Anirudh Rayabharam, linux-kernel, linux-kernel-mentees
This series fixes the use after free in firmware_fallback_sysfs reported
by syzbot at:
https://syzkaller.appspot.com/bug?extid=de271708674e2093097b
The first patch does some cleanup of the error codes and documents
them properly. The second patch goes on to actually fix the bug.
Changes in v5:
1. Split the patch into two patches as discussed here:
https://lore.kernel.org/lkml/20210715232105.am4wsxfclj2ufjdw@garbanzo/
Changes in v4:
Documented the reasons behind the error codes returned from
fw_sysfs_wait_timeout() as suggested by Luis Chamberlain.
Changes in v3:
Modified the patch to incorporate suggestions by Luis Chamberlain in
order to fix the root cause instead of applying a "band-aid" kind of
fix.
https://lore.kernel.org/lkml/20210403013143.GV4332@42.do-not-panic.com/
Changes in v2:
1. Fixed 1 error and 1 warning (in the commit message) reported by
checkpatch.pl. The error was regarding the format for referring to
another commit "commit <sha> ("oneline")". The warning was for line
longer than 75 chars.
Anirudh Rayabharam (2):
firmware_loader: use -ETIMEDOUT instead of -EAGAIN in
fw_load_sysfs_fallback
firmware_loader: fix use-after-free in firmware_fallback_sysfs
drivers/base/firmware_loader/fallback.c | 46 ++++++++++++++++++-------
drivers/base/firmware_loader/firmware.h | 6 +++-
drivers/base/firmware_loader/main.c | 2 ++
3 files changed, 40 insertions(+), 14 deletions(-)
--
2.26.2
^ permalink raw reply [flat|nested] 9+ messages in thread
* [PATCH v5 0/2] firmware_loader: fix uaf in firmware_fallback_sysfs
@ 2021-07-21 19:00 ` Anirudh Rayabharam
0 siblings, 0 replies; 9+ messages in thread
From: Anirudh Rayabharam @ 2021-07-21 19:00 UTC (permalink / raw)
To: mcgrof, gregkh, rafael, skhan; +Cc: linux-kernel-mentees, linux-kernel
This series fixes the use after free in firmware_fallback_sysfs reported
by syzbot at:
https://syzkaller.appspot.com/bug?extid=de271708674e2093097b
The first patch does some cleanup of the error codes and documents
them properly. The second patch goes on to actually fix the bug.
Changes in v5:
1. Split the patch into two patches as discussed here:
https://lore.kernel.org/lkml/20210715232105.am4wsxfclj2ufjdw@garbanzo/
Changes in v4:
Documented the reasons behind the error codes returned from
fw_sysfs_wait_timeout() as suggested by Luis Chamberlain.
Changes in v3:
Modified the patch to incorporate suggestions by Luis Chamberlain in
order to fix the root cause instead of applying a "band-aid" kind of
fix.
https://lore.kernel.org/lkml/20210403013143.GV4332@42.do-not-panic.com/
Changes in v2:
1. Fixed 1 error and 1 warning (in the commit message) reported by
checkpatch.pl. The error was regarding the format for referring to
another commit "commit <sha> ("oneline")". The warning was for line
longer than 75 chars.
Anirudh Rayabharam (2):
firmware_loader: use -ETIMEDOUT instead of -EAGAIN in
fw_load_sysfs_fallback
firmware_loader: fix use-after-free in firmware_fallback_sysfs
drivers/base/firmware_loader/fallback.c | 46 ++++++++++++++++++-------
drivers/base/firmware_loader/firmware.h | 6 +++-
drivers/base/firmware_loader/main.c | 2 ++
3 files changed, 40 insertions(+), 14 deletions(-)
--
2.26.2
_______________________________________________
Linux-kernel-mentees mailing list
Linux-kernel-mentees@lists.linuxfoundation.org
https://lists.linuxfoundation.org/mailman/listinfo/linux-kernel-mentees
^ permalink raw reply [flat|nested] 9+ messages in thread
* [PATCH v5 1/2] firmware_loader: use -ETIMEDOUT instead of -EAGAIN in fw_load_sysfs_fallback
2021-07-21 19:00 ` Anirudh Rayabharam
@ 2021-07-21 19:00 ` Anirudh Rayabharam
-1 siblings, 0 replies; 9+ messages in thread
From: Anirudh Rayabharam @ 2021-07-21 19:00 UTC (permalink / raw)
To: mcgrof, gregkh, rafael, skhan
Cc: Anirudh Rayabharam, linux-kernel, linux-kernel-mentees
The only motivation for using -EAGAIN in commit 0542ad88fbdd81bb
("firmware loader: Fix _request_firmware_load() return val for fw load
abort") was to distinguish the error from -ENOMEM, and so there is no
real reason in keeping it. Keeping -ETIMEDOU is much telling of what the
reason for a failure is, so just use that.
The rest is just trying to document a bit more of the motivations for the
error codes, as otherwise we'd lose this information easily.
Suggested-by: Luis Chamberlain <mcgrof@kernel.org>
Signed-off-by: Anirudh Rayabharam <mail@anirudhrb.com>
---
drivers/base/firmware_loader/fallback.c | 36 ++++++++++++++++++-------
1 file changed, 26 insertions(+), 10 deletions(-)
diff --git a/drivers/base/firmware_loader/fallback.c b/drivers/base/firmware_loader/fallback.c
index 91899d185e31..bc25bb5d1ed6 100644
--- a/drivers/base/firmware_loader/fallback.c
+++ b/drivers/base/firmware_loader/fallback.c
@@ -70,7 +70,31 @@ static inline bool fw_sysfs_loading(struct fw_priv *fw_priv)
static inline int fw_sysfs_wait_timeout(struct fw_priv *fw_priv, long timeout)
{
- return __fw_state_wait_common(fw_priv, timeout);
+ int ret = __fw_state_wait_common(fw_priv, timeout);
+
+ /*
+ * A signal could be sent to abort a wait. Consider Android's init
+ * gettting a SIGCHLD, which in turn was the same process issuing the
+ * sysfs store call for the fallback. In such cases we want to be able
+ * to tell apart in userspace when a signal caused a failure on the
+ * wait. In such cases we'd get -ERESTARTSYS.
+ *
+ * Likewise though another race can happen and abort the load earlier.
+ *
+ * In either case the situation is interrupted so we just inform
+ * userspace of that and we end things right away.
+ *
+ * When we really time out just tell userspace it should try again,
+ * perhaps later.
+ */
+ if (ret == -ERESTARTSYS || fw_state_is_aborted(fw_priv))
+ ret = -EINTR;
+ else if (ret == -ETIMEDOUT)
+ ret = -EAGAIN;
+ else if (fw_priv->is_paged_buf && !fw_priv->data)
+ ret = -ENOMEM;
+
+ return ret;
}
struct fw_sysfs {
@@ -526,20 +550,12 @@ static int fw_load_sysfs_fallback(struct fw_sysfs *fw_sysfs, long timeout)
}
retval = fw_sysfs_wait_timeout(fw_priv, timeout);
- if (retval < 0 && retval != -ENOENT) {
+ if (retval < 0) {
mutex_lock(&fw_lock);
fw_load_abort(fw_sysfs);
mutex_unlock(&fw_lock);
}
- if (fw_state_is_aborted(fw_priv)) {
- if (retval == -ERESTARTSYS)
- retval = -EINTR;
- else
- retval = -EAGAIN;
- } else if (fw_priv->is_paged_buf && !fw_priv->data)
- retval = -ENOMEM;
-
device_del(f_dev);
err_put_dev:
put_device(f_dev);
--
2.26.2
^ permalink raw reply related [flat|nested] 9+ messages in thread
* [PATCH v5 1/2] firmware_loader: use -ETIMEDOUT instead of -EAGAIN in fw_load_sysfs_fallback
@ 2021-07-21 19:00 ` Anirudh Rayabharam
0 siblings, 0 replies; 9+ messages in thread
From: Anirudh Rayabharam @ 2021-07-21 19:00 UTC (permalink / raw)
To: mcgrof, gregkh, rafael, skhan; +Cc: linux-kernel-mentees, linux-kernel
The only motivation for using -EAGAIN in commit 0542ad88fbdd81bb
("firmware loader: Fix _request_firmware_load() return val for fw load
abort") was to distinguish the error from -ENOMEM, and so there is no
real reason in keeping it. Keeping -ETIMEDOU is much telling of what the
reason for a failure is, so just use that.
The rest is just trying to document a bit more of the motivations for the
error codes, as otherwise we'd lose this information easily.
Suggested-by: Luis Chamberlain <mcgrof@kernel.org>
Signed-off-by: Anirudh Rayabharam <mail@anirudhrb.com>
---
drivers/base/firmware_loader/fallback.c | 36 ++++++++++++++++++-------
1 file changed, 26 insertions(+), 10 deletions(-)
diff --git a/drivers/base/firmware_loader/fallback.c b/drivers/base/firmware_loader/fallback.c
index 91899d185e31..bc25bb5d1ed6 100644
--- a/drivers/base/firmware_loader/fallback.c
+++ b/drivers/base/firmware_loader/fallback.c
@@ -70,7 +70,31 @@ static inline bool fw_sysfs_loading(struct fw_priv *fw_priv)
static inline int fw_sysfs_wait_timeout(struct fw_priv *fw_priv, long timeout)
{
- return __fw_state_wait_common(fw_priv, timeout);
+ int ret = __fw_state_wait_common(fw_priv, timeout);
+
+ /*
+ * A signal could be sent to abort a wait. Consider Android's init
+ * gettting a SIGCHLD, which in turn was the same process issuing the
+ * sysfs store call for the fallback. In such cases we want to be able
+ * to tell apart in userspace when a signal caused a failure on the
+ * wait. In such cases we'd get -ERESTARTSYS.
+ *
+ * Likewise though another race can happen and abort the load earlier.
+ *
+ * In either case the situation is interrupted so we just inform
+ * userspace of that and we end things right away.
+ *
+ * When we really time out just tell userspace it should try again,
+ * perhaps later.
+ */
+ if (ret == -ERESTARTSYS || fw_state_is_aborted(fw_priv))
+ ret = -EINTR;
+ else if (ret == -ETIMEDOUT)
+ ret = -EAGAIN;
+ else if (fw_priv->is_paged_buf && !fw_priv->data)
+ ret = -ENOMEM;
+
+ return ret;
}
struct fw_sysfs {
@@ -526,20 +550,12 @@ static int fw_load_sysfs_fallback(struct fw_sysfs *fw_sysfs, long timeout)
}
retval = fw_sysfs_wait_timeout(fw_priv, timeout);
- if (retval < 0 && retval != -ENOENT) {
+ if (retval < 0) {
mutex_lock(&fw_lock);
fw_load_abort(fw_sysfs);
mutex_unlock(&fw_lock);
}
- if (fw_state_is_aborted(fw_priv)) {
- if (retval == -ERESTARTSYS)
- retval = -EINTR;
- else
- retval = -EAGAIN;
- } else if (fw_priv->is_paged_buf && !fw_priv->data)
- retval = -ENOMEM;
-
device_del(f_dev);
err_put_dev:
put_device(f_dev);
--
2.26.2
_______________________________________________
Linux-kernel-mentees mailing list
Linux-kernel-mentees@lists.linuxfoundation.org
https://lists.linuxfoundation.org/mailman/listinfo/linux-kernel-mentees
^ permalink raw reply related [flat|nested] 9+ messages in thread
* [PATCH v5 2/2] firmware_loader: fix use-after-free in firmware_fallback_sysfs
2021-07-21 19:00 ` Anirudh Rayabharam
@ 2021-07-21 19:00 ` Anirudh Rayabharam
-1 siblings, 0 replies; 9+ messages in thread
From: Anirudh Rayabharam @ 2021-07-21 19:00 UTC (permalink / raw)
To: mcgrof, gregkh, rafael, skhan
Cc: Anirudh Rayabharam, linux-kernel, linux-kernel-mentees,
syzbot+de271708674e2093097b
This use-after-free happens when a fw_priv object has been freed but
hasn't been removed from the pending list (pending_fw_head). The next
time fw_load_sysfs_fallback tries to insert into the list, it ends up
accessing the pending_list member of the previoiusly freed fw_priv.
The root cause here is that all code paths that abort the fw load
don't delete it from the pending list. For example:
_request_firmware()
-> fw_abort_batch_reqs()
-> fw_state_aborted()
To fix this, delete the fw_priv from the list in __fw_set_state() if
the new state is DONE or ABORTED. This way, all aborts will remove
the fw_priv from the list. Accordingly, remove calls to list_del_init
that were being made before calling fw_state_(aborted|done).
Also, in fw_load_sysfs_fallback, don't add the fw_priv to the pending
list if it is already aborted. Instead, just jump out and return early.
Fixes: bcfbd3523f3c ("firmware: fix a double abort case with fw_load_sysfs_fallback")
Reported-by: syzbot+de271708674e2093097b@syzkaller.appspotmail.com
Tested-by: syzbot+de271708674e2093097b@syzkaller.appspotmail.com
Signed-off-by: Anirudh Rayabharam <mail@anirudhrb.com>
---
drivers/base/firmware_loader/fallback.c | 10 +++++++---
drivers/base/firmware_loader/firmware.h | 6 +++++-
drivers/base/firmware_loader/main.c | 2 ++
3 files changed, 14 insertions(+), 4 deletions(-)
diff --git a/drivers/base/firmware_loader/fallback.c b/drivers/base/firmware_loader/fallback.c
index bc25bb5d1ed6..f244c7b89ba5 100644
--- a/drivers/base/firmware_loader/fallback.c
+++ b/drivers/base/firmware_loader/fallback.c
@@ -115,10 +115,9 @@ static void __fw_load_abort(struct fw_priv *fw_priv)
* There is a small window in which user can write to 'loading'
* between loading done and disappearance of 'loading'
*/
- if (fw_sysfs_done(fw_priv))
+ if (fw_state_is_aborted(fw_priv) || fw_sysfs_done(fw_priv))
return;
- list_del_init(&fw_priv->pending_list);
fw_state_aborted(fw_priv);
}
@@ -304,7 +303,6 @@ static ssize_t firmware_loading_store(struct device *dev,
* Same logic as fw_load_abort, only the DONE bit
* is ignored and we set ABORT only on failure.
*/
- list_del_init(&fw_priv->pending_list);
if (rc) {
fw_state_aborted(fw_priv);
written = rc;
@@ -537,6 +535,11 @@ static int fw_load_sysfs_fallback(struct fw_sysfs *fw_sysfs, long timeout)
}
mutex_lock(&fw_lock);
+ if (fw_state_is_aborted(fw_priv)) {
+ mutex_unlock(&fw_lock);
+ retval = -EINTR;
+ goto out;
+ }
list_add(&fw_priv->pending_list, &pending_fw_head);
mutex_unlock(&fw_lock);
@@ -556,6 +559,7 @@ static int fw_load_sysfs_fallback(struct fw_sysfs *fw_sysfs, long timeout)
mutex_unlock(&fw_lock);
}
+out:
device_del(f_dev);
err_put_dev:
put_device(f_dev);
diff --git a/drivers/base/firmware_loader/firmware.h b/drivers/base/firmware_loader/firmware.h
index 63bd29fdcb9c..36bdb413c998 100644
--- a/drivers/base/firmware_loader/firmware.h
+++ b/drivers/base/firmware_loader/firmware.h
@@ -117,8 +117,12 @@ static inline void __fw_state_set(struct fw_priv *fw_priv,
WRITE_ONCE(fw_st->status, status);
- if (status == FW_STATUS_DONE || status == FW_STATUS_ABORTED)
+ if (status == FW_STATUS_DONE || status == FW_STATUS_ABORTED) {
+#ifdef CONFIG_FW_LOADER_USER_HELPER
+ list_del_init(&fw_priv->pending_list);
+#endif
complete_all(&fw_st->completion);
+ }
}
static inline void fw_state_aborted(struct fw_priv *fw_priv)
diff --git a/drivers/base/firmware_loader/main.c b/drivers/base/firmware_loader/main.c
index 4fdb8219cd08..68c549d71230 100644
--- a/drivers/base/firmware_loader/main.c
+++ b/drivers/base/firmware_loader/main.c
@@ -783,8 +783,10 @@ static void fw_abort_batch_reqs(struct firmware *fw)
return;
fw_priv = fw->priv;
+ mutex_lock(&fw_lock);
if (!fw_state_is_aborted(fw_priv))
fw_state_aborted(fw_priv);
+ mutex_unlock(&fw_lock);
}
/* called from request_firmware() and request_firmware_work_func() */
--
2.26.2
^ permalink raw reply related [flat|nested] 9+ messages in thread
* [PATCH v5 2/2] firmware_loader: fix use-after-free in firmware_fallback_sysfs
@ 2021-07-21 19:00 ` Anirudh Rayabharam
0 siblings, 0 replies; 9+ messages in thread
From: Anirudh Rayabharam @ 2021-07-21 19:00 UTC (permalink / raw)
To: mcgrof, gregkh, rafael, skhan
Cc: linux-kernel-mentees, linux-kernel, syzbot+de271708674e2093097b
This use-after-free happens when a fw_priv object has been freed but
hasn't been removed from the pending list (pending_fw_head). The next
time fw_load_sysfs_fallback tries to insert into the list, it ends up
accessing the pending_list member of the previoiusly freed fw_priv.
The root cause here is that all code paths that abort the fw load
don't delete it from the pending list. For example:
_request_firmware()
-> fw_abort_batch_reqs()
-> fw_state_aborted()
To fix this, delete the fw_priv from the list in __fw_set_state() if
the new state is DONE or ABORTED. This way, all aborts will remove
the fw_priv from the list. Accordingly, remove calls to list_del_init
that were being made before calling fw_state_(aborted|done).
Also, in fw_load_sysfs_fallback, don't add the fw_priv to the pending
list if it is already aborted. Instead, just jump out and return early.
Fixes: bcfbd3523f3c ("firmware: fix a double abort case with fw_load_sysfs_fallback")
Reported-by: syzbot+de271708674e2093097b@syzkaller.appspotmail.com
Tested-by: syzbot+de271708674e2093097b@syzkaller.appspotmail.com
Signed-off-by: Anirudh Rayabharam <mail@anirudhrb.com>
---
drivers/base/firmware_loader/fallback.c | 10 +++++++---
drivers/base/firmware_loader/firmware.h | 6 +++++-
drivers/base/firmware_loader/main.c | 2 ++
3 files changed, 14 insertions(+), 4 deletions(-)
diff --git a/drivers/base/firmware_loader/fallback.c b/drivers/base/firmware_loader/fallback.c
index bc25bb5d1ed6..f244c7b89ba5 100644
--- a/drivers/base/firmware_loader/fallback.c
+++ b/drivers/base/firmware_loader/fallback.c
@@ -115,10 +115,9 @@ static void __fw_load_abort(struct fw_priv *fw_priv)
* There is a small window in which user can write to 'loading'
* between loading done and disappearance of 'loading'
*/
- if (fw_sysfs_done(fw_priv))
+ if (fw_state_is_aborted(fw_priv) || fw_sysfs_done(fw_priv))
return;
- list_del_init(&fw_priv->pending_list);
fw_state_aborted(fw_priv);
}
@@ -304,7 +303,6 @@ static ssize_t firmware_loading_store(struct device *dev,
* Same logic as fw_load_abort, only the DONE bit
* is ignored and we set ABORT only on failure.
*/
- list_del_init(&fw_priv->pending_list);
if (rc) {
fw_state_aborted(fw_priv);
written = rc;
@@ -537,6 +535,11 @@ static int fw_load_sysfs_fallback(struct fw_sysfs *fw_sysfs, long timeout)
}
mutex_lock(&fw_lock);
+ if (fw_state_is_aborted(fw_priv)) {
+ mutex_unlock(&fw_lock);
+ retval = -EINTR;
+ goto out;
+ }
list_add(&fw_priv->pending_list, &pending_fw_head);
mutex_unlock(&fw_lock);
@@ -556,6 +559,7 @@ static int fw_load_sysfs_fallback(struct fw_sysfs *fw_sysfs, long timeout)
mutex_unlock(&fw_lock);
}
+out:
device_del(f_dev);
err_put_dev:
put_device(f_dev);
diff --git a/drivers/base/firmware_loader/firmware.h b/drivers/base/firmware_loader/firmware.h
index 63bd29fdcb9c..36bdb413c998 100644
--- a/drivers/base/firmware_loader/firmware.h
+++ b/drivers/base/firmware_loader/firmware.h
@@ -117,8 +117,12 @@ static inline void __fw_state_set(struct fw_priv *fw_priv,
WRITE_ONCE(fw_st->status, status);
- if (status == FW_STATUS_DONE || status == FW_STATUS_ABORTED)
+ if (status == FW_STATUS_DONE || status == FW_STATUS_ABORTED) {
+#ifdef CONFIG_FW_LOADER_USER_HELPER
+ list_del_init(&fw_priv->pending_list);
+#endif
complete_all(&fw_st->completion);
+ }
}
static inline void fw_state_aborted(struct fw_priv *fw_priv)
diff --git a/drivers/base/firmware_loader/main.c b/drivers/base/firmware_loader/main.c
index 4fdb8219cd08..68c549d71230 100644
--- a/drivers/base/firmware_loader/main.c
+++ b/drivers/base/firmware_loader/main.c
@@ -783,8 +783,10 @@ static void fw_abort_batch_reqs(struct firmware *fw)
return;
fw_priv = fw->priv;
+ mutex_lock(&fw_lock);
if (!fw_state_is_aborted(fw_priv))
fw_state_aborted(fw_priv);
+ mutex_unlock(&fw_lock);
}
/* called from request_firmware() and request_firmware_work_func() */
--
2.26.2
_______________________________________________
Linux-kernel-mentees mailing list
Linux-kernel-mentees@lists.linuxfoundation.org
https://lists.linuxfoundation.org/mailman/listinfo/linux-kernel-mentees
^ permalink raw reply related [flat|nested] 9+ messages in thread
* Re: [PATCH v5 1/2] firmware_loader: use -ETIMEDOUT instead of -EAGAIN in fw_load_sysfs_fallback
2021-07-21 19:00 ` Anirudh Rayabharam
(?)
@ 2021-07-21 19:14 ` Luis Chamberlain
2021-07-22 12:33 ` Anirudh Rayabharam
-1 siblings, 1 reply; 9+ messages in thread
From: Luis Chamberlain @ 2021-07-21 19:14 UTC (permalink / raw)
To: Anirudh Rayabharam; +Cc: linux-kernel-mentees, linux-kernel, Rafael J. Wysocki
[-- Attachment #1.1: Type: text/plain, Size: 3285 bytes --]
But the patch still keeps it, please remove the -EAGAIN setting completely.
On Wed, Jul 21, 2021, 12:01 PM Anirudh Rayabharam <mail@anirudhrb.com>
wrote:
> The only motivation for using -EAGAIN in commit 0542ad88fbdd81bb
> ("firmware loader: Fix _request_firmware_load() return val for fw load
> abort") was to distinguish the error from -ENOMEM, and so there is no
> real reason in keeping it. Keeping -ETIMEDOU is much telling of what the
> reason for a failure is, so just use that.
>
> The rest is just trying to document a bit more of the motivations for the
> error codes, as otherwise we'd lose this information easily.
>
> Suggested-by: Luis Chamberlain <mcgrof@kernel.org>
> Signed-off-by: Anirudh Rayabharam <mail@anirudhrb.com>
> ---
> drivers/base/firmware_loader/fallback.c | 36 ++++++++++++++++++-------
> 1 file changed, 26 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/base/firmware_loader/fallback.c
> b/drivers/base/firmware_loader/fallback.c
> index 91899d185e31..bc25bb5d1ed6 100644
> --- a/drivers/base/firmware_loader/fallback.c
> +++ b/drivers/base/firmware_loader/fallback.c
> @@ -70,7 +70,31 @@ static inline bool fw_sysfs_loading(struct fw_priv
> *fw_priv)
>
> static inline int fw_sysfs_wait_timeout(struct fw_priv *fw_priv, long
> timeout)
> {
> - return __fw_state_wait_common(fw_priv, timeout);
> + int ret = __fw_state_wait_common(fw_priv, timeout);
> +
> + /*
> + * A signal could be sent to abort a wait. Consider Android's init
> + * gettting a SIGCHLD, which in turn was the same process issuing
> the
> + * sysfs store call for the fallback. In such cases we want to be
> able
> + * to tell apart in userspace when a signal caused a failure on the
> + * wait. In such cases we'd get -ERESTARTSYS.
> + *
> + * Likewise though another race can happen and abort the load
> earlier.
> + *
> + * In either case the situation is interrupted so we just inform
> + * userspace of that and we end things right away.
> + *
> + * When we really time out just tell userspace it should try again,
> + * perhaps later.
> + */
> + if (ret == -ERESTARTSYS || fw_state_is_aborted(fw_priv))
> + ret = -EINTR;
> + else if (ret == -ETIMEDOUT)
> + ret = -EAGAIN;
> + else if (fw_priv->is_paged_buf && !fw_priv->data)
> + ret = -ENOMEM;
> +
> + return ret;
> }
>
> struct fw_sysfs {
> @@ -526,20 +550,12 @@ static int fw_load_sysfs_fallback(struct fw_sysfs
> *fw_sysfs, long timeout)
> }
>
> retval = fw_sysfs_wait_timeout(fw_priv, timeout);
> - if (retval < 0 && retval != -ENOENT) {
> + if (retval < 0) {
> mutex_lock(&fw_lock);
> fw_load_abort(fw_sysfs);
> mutex_unlock(&fw_lock);
> }
>
> - if (fw_state_is_aborted(fw_priv)) {
> - if (retval == -ERESTARTSYS)
> - retval = -EINTR;
> - else
> - retval = -EAGAIN;
> - } else if (fw_priv->is_paged_buf && !fw_priv->data)
> - retval = -ENOMEM;
> -
> device_del(f_dev);
> err_put_dev:
> put_device(f_dev);
> --
> 2.26.2
>
>
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^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH v5 1/2] firmware_loader: use -ETIMEDOUT instead of -EAGAIN in fw_load_sysfs_fallback
2021-07-21 19:14 ` Luis Chamberlain
@ 2021-07-22 12:33 ` Anirudh Rayabharam
0 siblings, 0 replies; 9+ messages in thread
From: Anirudh Rayabharam @ 2021-07-22 12:33 UTC (permalink / raw)
To: Luis Chamberlain
Cc: Greg Kroah-Hartman, Rafael J. Wysocki, Shuah Khan, linux-kernel,
linux-kernel-mentees
On Wed, Jul 21, 2021 at 12:14:37PM -0700, Luis Chamberlain wrote:
> But the patch still keeps it, please remove the -EAGAIN setting completely.
Oops, my bad! Sent a new version.
- Anirudh.
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH v5 1/2] firmware_loader: use -ETIMEDOUT instead of -EAGAIN in fw_load_sysfs_fallback
@ 2021-07-22 12:33 ` Anirudh Rayabharam
0 siblings, 0 replies; 9+ messages in thread
From: Anirudh Rayabharam @ 2021-07-22 12:33 UTC (permalink / raw)
To: Luis Chamberlain; +Cc: linux-kernel-mentees, linux-kernel, Rafael J. Wysocki
On Wed, Jul 21, 2021 at 12:14:37PM -0700, Luis Chamberlain wrote:
> But the patch still keeps it, please remove the -EAGAIN setting completely.
Oops, my bad! Sent a new version.
- Anirudh.
_______________________________________________
Linux-kernel-mentees mailing list
Linux-kernel-mentees@lists.linuxfoundation.org
https://lists.linuxfoundation.org/mailman/listinfo/linux-kernel-mentees
^ permalink raw reply [flat|nested] 9+ messages in thread
end of thread, other threads:[~2021-07-22 12:34 UTC | newest]
Thread overview: 9+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-07-21 19:00 [PATCH v5 0/2] firmware_loader: fix uaf in firmware_fallback_sysfs Anirudh Rayabharam
2021-07-21 19:00 ` Anirudh Rayabharam
2021-07-21 19:00 ` [PATCH v5 1/2] firmware_loader: use -ETIMEDOUT instead of -EAGAIN in fw_load_sysfs_fallback Anirudh Rayabharam
2021-07-21 19:00 ` Anirudh Rayabharam
2021-07-21 19:14 ` Luis Chamberlain
2021-07-22 12:33 ` Anirudh Rayabharam
2021-07-22 12:33 ` Anirudh Rayabharam
2021-07-21 19:00 ` [PATCH v5 2/2] firmware_loader: fix use-after-free in firmware_fallback_sysfs Anirudh Rayabharam
2021-07-21 19:00 ` Anirudh Rayabharam
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